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    &nbsp;&nbsp;//&nbsp;&nbsp;<a href="./index.html">Document Index</a></div><h1 id="iredmail-easy-what-is-ssh-jump-server">iRedMail Easy: What is SSH jump server</h1>
<p>It's common that you have a protected Linux/BSD server that isn’t publicly
accessible. Typically, you may have what is commonly referred to as a
<em><strong>jump server</strong></em> or <em><strong>bastion server</strong></em> which is accessible from a public
network (sometimes this jump server would be in a DMZ, and also Linux/BSD),
you connect to this jump server first, then connect to the protected server
from jump server.</p>
<p>Sample setup:</p>
<pre><code>+--------+       +-------------+      +------------------+
| Laptop | &lt;---&gt; | Jump server | &lt;--&gt; | Protected server |
+--------+       +-------------+      +------------------+
</code></pre>
<p>You can connect to the protected server through jump server via ssh with
command like below:</p>
<pre><code>ssh -v -J user1@jump-server user2@protected-server
</code></pre>
<h2 id="references">References</h2>
<ul>
<li><a href="https://man.openbsd.org/ssh#J">SSH manual page</a></li>
</ul><div class="footer">
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